JP2949827B2 - Wurtzite-type boron carbonitride powder and method for producing the same - Google Patents
Wurtzite-type boron carbonitride powder and method for producing the sameInfo
- Publication number
- JP2949827B2 JP2949827B2 JP2289831A JP28983190A JP2949827B2 JP 2949827 B2 JP2949827 B2 JP 2949827B2 JP 2289831 A JP2289831 A JP 2289831A JP 28983190 A JP28983190 A JP 28983190A JP 2949827 B2 JP2949827 B2 JP 2949827B2
- Authority
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- Prior art keywords
- powder
- bcn
- pressure
- grain size
- crystal grain
- Prior art date
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J3/00—Processes of utilising sub-atmospheric or super-atmospheric pressure to effect chemical or physical change of matter; Apparatus therefor
- B01J3/06—Processes using ultra-high pressure, e.g. for the formation of diamonds; Apparatus therefor, e.g. moulds or dies
- B01J3/062—Processes using ultra-high pressure, e.g. for the formation of diamonds; Apparatus therefor, e.g. moulds or dies characterised by the composition of the materials to be processed
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J2203/00—Processes utilising sub- or super atmospheric pressure
- B01J2203/06—High pressure synthesis
- B01J2203/065—Composition of the material produced
- B01J2203/066—Boronitrides
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Polishing Bodies And Polishing Tools (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、硬質にして、結晶粒径が20μｍ以上の粗
粒であり、したがって、例えば砥石の硬質粒子として用
いるのに適したウルツアイト型炭窒化ほう素（以下、ｗ
−BCNで示す）粉末、およびその製造法に関するもので
ある。The present invention relates to a wurtzite-type coal which is hard and is a coarse particle having a crystal grain size of 20 μm or more, and thus is suitable for use as, for example, hard particles of a grinding wheel. Boron nitride (hereinafter, w
-Indicated by BCN) and a process for its preparation.
従来、一般に原料粉末とて、窒化ほう素（以下、BNで
示す）粉末および炭素粉末を用い、これら原料粉末を、
重量％で、主要割合で示せば、 炭素粉末:33％、 BN粉末：残り、 に配合し、混合した後、通常の高温高圧装置にて、 温度:3000℃以上、 圧力:1万気圧以上、 の条件で加熱して、構成元素の主要割合が、原子％で、 C:33％、 N:33％、 B:残り、 からなる六方晶型炭窒化ほう素（以下、ｈ−BCNで示
す）粉末を製造する方法が知られている。Conventionally, a boron nitride (hereinafter, referred to as BN) powder and a carbon powder are generally used as raw material powders.
In weight%, the major proportions are as follows: carbon powder: 33%, BN powder: remaining, blended into and mixed, and then with a normal high-temperature and high-pressure device, temperature: 3000 ° C or more, pressure: 10,000 atmospheres or more, Hexagonal boron carbonitride consisting of C: 33%, N: 33%, B: remain, and Methods for producing powders are known.
また、特開昭53−101000号公報に記載される通り、上
記の従来方法などで製造されたｈ−BCN粉末を、Fe−Al
合金粉末などの触媒と混合した状態で、同じく通常の高
温高圧装置を用いて、 温度:1300〜2000℃、 圧力:5〜10万気圧、 の条件で加圧して変態せしめることにより立方晶型炭窒
化ほう素（以下、ｃ−BCNで示す）を製造する方法が知
られている。Further, as described in JP-A-53-101000, the h-BCN powder produced by the above-mentioned conventional method or the like is treated with Fe-Al
In a state mixed with a catalyst such as an alloy powder, cubic coal is formed by applying pressure to a temperature of 1300 to 2000 ° C and a pressure of 50,000 to 100,000 atm using the same high-temperature and high-pressure equipment. A method for producing boron nitride (hereinafter, referred to as c-BCN) is known.
しかし、上記の従来方法で製造されたｈ−BCN粉末
は、結晶粒径で３μｍ以下とあまりにも細粒であり、か
つ軟質であるために、例えば砥石の製造に硬質粒子とし
て適用することはできず、一方同じく上記の従来方法で
製造されたｃ−BCN粉末は、結晶粒径で100μｍ以下と相
対的に粗粒ではあるが、上記触媒の混入が原因で、きわ
めて脆く、欠け易いので砥石への実用化は困難であるの
が現状である。However, the h-BCN powder produced by the above-mentioned conventional method has a crystal grain size of 3 μm or less, which is too fine, and is soft, so that it can be applied as a hard particle in the production of a grindstone, for example. On the other hand, c-BCN powder produced by the above-mentioned conventional method is relatively coarse with a crystal grain size of 100 μm or less, but is extremely brittle due to the incorporation of the catalyst, and is easily chipped. At present, it is difficult to put this into practical use.
そこで、本発明者等は、上述のような観点から、現在
あまり注目されていないｗ−BCN粉末に着目し、研究を
行なった結果、 （１） 上記の従来方法で製造されたｈ−BCN粉末、す
なわち構成元素の主要割合が、原子％で、 C:33％、 N:33％、 B:残り、 からなるｈ−BCN粉末の結晶構造をウルツアイト型に変
態せしめるべく、これに10万気圧以上の圧力で加圧処理
を施しても、結晶粒径で１μｍ以下の細粒のｗ−BCN粉
末しか得られないこと。In view of the above, the present inventors have focused on w-BCN powder, which has not received much attention at present, and conducted research. As a result, (1) the h-BCN powder produced by the above-described conventional method In other words, in order to transform the crystal structure of the h-BCN powder composed of C: 33%, N: 33%, B: remaining, and , Only fine w-BCN powder having a crystal grain size of 1 μm or less can be obtained.
（２） しかし、上記の従来ｈ−BCN粉末の製造方法に
おいて、原料粉末である炭素粉末の配合割合を全体に占
める割合で２〜30重量％と低くする（この結果BN粉末の
配合割合が相対的に高くなる）と、製造されたｈ−BCN
粉末は、構成元素であるＢとＣとＮの割合が、原子％
で、 C:2〜20％、 N:40〜49％、 B:残り（ただし40〜49％）、 からなると共に、結晶粒径で20μｍ以上の粗粒となるこ
と。(2) However, in the above-mentioned conventional method for producing h-BCN powder, the blending ratio of the carbon powder as the raw material powder is reduced to 2 to 30% by weight as a percentage of the whole (as a result, the blending ratio of the BN powder is H-BCN produced)
In the powder, the ratio of the constituent elements B, C, and N is atomic%.
C: 2 to 20%, N: 40 to 49%, B: Remaining (but 40 to 49%), and coarse grains with a crystal grain size of 20 μm or more.
（３） 上記（２）で製造された20μｍ以上の結晶粒径
を有する粗粒のｈ−BCN粉末に、10万気圧以上の圧力で
加圧処理を施すと、構成元素の割合が、原子％で、 C:2〜20％、 N:40〜49％、 B:残り（ただし40〜49％）、 からなり、かつ20μｍ以上の結晶粒径をもった粗粒のｗ
−BCN粉末が得られること。(3) When the coarse h-BCN powder having a crystal grain size of 20 μm or more produced in the above (2) is subjected to a pressure treatment at a pressure of 100,000 atmospheres or more, the ratio of constituent elements becomes atomic%. And C: 2 to 20%, N: 40 to 49%, B: Remaining (but 40 to 49%), and w of coarse particles having a crystal grain size of 20 μm or more
-BCN powder is obtained.
（４） 上記（３）で製造されたｗ−BCN粉末は、触媒
などを一切混入せずに製造されたものであるので、きわ
めて硬質で、欠け難く、かつ粗粒であることと相まっ
て、例えば砥石の硬質粒子などとして用いた場合にすぐ
れた性能を発揮すること。以上（１）〜（４）の研究結
果を得たのである。(4) The w-BCN powder produced in the above (3) is produced without mixing a catalyst or the like at all, and is combined with being extremely hard, hard to chip, and coarse. Demonstrates excellent performance when used as hard particles of grinding wheels. The research results (1) to (4) above were obtained.
この発明は、上記の研究結果にもとづいてなされたも
のであって、 原料粉末として、BN粉末と炭素粉末を用い、これら原
料粉末を、 炭素粉末:2〜30重量％、 BN:残り、 の割合に配合し、混合した後、通常の高温高圧装置に
て、 温度:3000℃以上、 圧力:1万気圧以上、 の条件で加熱して、構成元素の主要割合が、原子％で、 C:2〜20％、 N:40〜49％、 B:残り（ただし40〜49％）、 からなり、かつ20μｍ以上の結晶粒径をもった粗粒のｈ
−BCN粉末を形成し、 ついで、このｈ−BCN粉末に、10万気圧以上の圧力で
加圧処理を施して、変態せしめることによりｗ−BCN粉
末を製造する方法、並びにこの方法で製造された、構成
元素であるＢとＣとＮの割合が、原子％で、 C:2〜20％、N:40〜49％、 B:残り（ただし40〜49％）、 からなり、かつ20μｍ以上の結晶粒径を有する粗粒のｗ
−BCN粉末、 に特徴を有するものである。The present invention has been made based on the above-mentioned research results, and uses BN powder and carbon powder as raw material powders. These raw material powders are: carbon powder: 2 to 30% by weight; After mixing, the mixture is heated in a normal high-temperature and high-pressure apparatus under the following conditions: temperature: 3000 ° C or more, pressure: 10,000 atmospheres or more. -20%, N: 40-49%, B: Remaining (but 40-49%), and coarse grains having a crystal grain size of 20 μm or more
A method of producing a w-BCN powder by subjecting the h-BCN powder to a pressure treatment at a pressure of 100,000 atmospheres or more and transforming the h-BCN powder; And the proportions of the constituent elements B, C and N are atomic%, C: 2 to 20%, N: 40 to 49%, B: remaining (but 40 to 49%), and more than 20 μm Coarse-grain w having crystal grain size
-BCN powder.
なお、この発明のｗ−BCN粉末の構成元素の割合、お
よび製造条件を上記の通りに限定したのは以下の理由に
よるものである。The ratios of the constituent elements of the w-BCN powder of the present invention and the manufacturing conditions are limited as described above for the following reasons.
A.構成元素の割合 原子％で、Ｃ成分の割合が２％未満、すなわち等量割
合のＢ成分とＮ成分がそれぞれ49％を越えて多くなりす
ぎると、粉末に所望の高硬度を確保することができず、
一方Ｃ成分の割合が20％を越えると、相対的に等量割合
のＢ成分とＮ成分の割合が40％未満と少なくなりすぎ、
製造された粉末の結晶粒径が細粒化し、20μｍ以上の結
晶粒径の粉末を得ることができなくなることから、その
割合を、C:2〜20％、N:40〜49％、B:残り（ただしＮと
同当量の40〜49％）と定めた。A. Proportion of Constituent Elements If the proportion of the C component is less than 2% in atomic%, that is, if the proportions of the B component and the N component are more than 49%, respectively, the powder will have a desired high hardness. Can not
On the other hand, when the proportion of the C component exceeds 20%, the proportion of the B component and the N component in relatively equal proportions becomes too small, less than 40%,
Since the crystal grain size of the produced powder becomes finer and it becomes impossible to obtain a powder having a crystal grain size of 20 μm or more, the proportions are as follows: C: 2 to 20%, N: 40 to 49%, B: The remainder (but 40 to 49% of N equivalent) was determined.
B.製造条件 （ａ） 炭素粉末の配合割合 その配合割合が２重量％未満では、中間的に製造され
るｈ−BCN粉末および最終的に製造されるｗ−BCN粉末に
おけるＣ成分の割合が２原子％未満となってしまい、製
造される粉末の硬さが低下するようになり、一方その配
合割合が30％を越えると、上記ｈ−BCN粉末の結晶粒径
が細粒化し、強いてはｗ−BCN粉末の結晶粒径も微細化
するようになって、結晶粒径が20μｍ以上の粗粒のｗ−
BCN粉末を製造することができなくなることから、その
配合割合を２〜30重量％と定めた。B. Production Conditions (a) Blending Ratio of Carbon Powder If the blending ratio is less than 2% by weight, the ratio of the C component in the intermediately produced h-BCN powder and the finally produced w-BCN powder is 2%. If the content is less than 30%, the crystal grain size of the h-BCN powder becomes finer, and if it is more than 30%, w -The crystal grain size of the BCN powder has also been refined, and the coarse w-
Since it becomes impossible to produce BCN powder, the blending ratio was determined to be 2 to 30% by weight.
（ｂ） ｈ−BCN粉末の製造条件 3000℃未満の温度、および１万気圧未満の圧力では、
BNとＣの合成によるｈ−BCN粉末の製造が十分に行なわ
れないことから、温度:3000℃以上、圧力:1万気圧以上
と定めた。(B) Production conditions of h-BCN powder At a temperature lower than 3000 ° C. and a pressure lower than 10,000 atm,
Since the production of h-BCN powder by the synthesis of BN and C is not sufficiently performed, the temperature was set to 3000 ° C. or more, and the pressure was set to 10,000 atmospheres or more.
（ｃ） ｗ−BCN粉末の製造条件 10万気圧未満の圧力ではｈ−BCN粉末のｗ−BCN粉末へ
の変換が不十分であることから、その圧力を10万気圧以
上と定めた。(C) Production conditions for w-BCN powder At a pressure of less than 100,000 atmospheres, the conversion of h-BCN powder to w-BCN powder is insufficient, so the pressure was set to 100,000 atmospheres or more.
つぎに、この発明のｗ−BCN粉末およびその製造法を
実施例により具体的に説明する。Next, the w-BCN powder of the present invention and a method for producing the same will be specifically described with reference to examples.
原料粉末として、それぞれ第１表に示される平均粒径
および結晶型を有するBN粉末、および黒鉛粉末を用い、
これら原料粉末を同じく第１表に示される割合に配合
し、通常の条件で混合した後、通常のピストンシリンダ
型高温高圧装置にて、第１表に示される条件で加熱して
同じく第１表に示される粒度分布をもったｈ−BCN粉末
を製造し、引続いて、これらのｈ−BCN粉末に、通常の
ブリッジマン型高圧装置を用いて、第１表に示される圧
力を付加することにより本発明法１〜６を実施し、本発
明ｗ−BCN粉末を製造した。As the raw material powder, a BN powder having an average particle size and a crystal form shown in Table 1 and a graphite powder were used,
These raw material powders were also blended in the proportions shown in Table 1 and mixed under ordinary conditions, and then heated under the conditions shown in Table 1 using a conventional piston-cylinder type high-temperature and high-pressure apparatus. The h-BCN powder having the particle size distribution shown in Table 1 was produced, and then the pressure shown in Table 1 was applied to these h-BCN powders using a normal Bridgman-type high-pressure apparatus. In accordance with the present invention, the methods 1 to 6 were carried out to produce w-BCN powder of the present invention.
この結果得られた本発明ｗ−BCN粉末１〜６は、第２
表に示される構成元素割合および粒度分布をもつもので
あった。The resulting w-BCN powders 1 to 6 of the present invention
It had the constituent element ratio and particle size distribution shown in the table.
また、本発明ｗ−BCN粉末１〜６のうちの 本発明ｗ・BCN粉末１を用い、これより分級にて100±10
μｍの結晶粒径範囲の粉末を取り出し、これをCu−Sn系
合金のメタルボンドを用いて、集中度:35にして、幅:3m
m×長さ:10mmの寸法をもった研削用砥石に仕上げ、この
砥石で、 速度:50m/min、 ホーン圧力:5kg/cm2、 の条件で鋳鉄（FC25）の研削を行ない、研削効率（比材
料除去能率）を測定したところ、5mm/minを示した。In addition, of the present w-BCN powders 1 to 6, The present w.BCN powder 1 was used.
Take out the powder having a crystal grain size range of μm, and use a metal bond of a Cu-Sn alloy to make the concentration degree: 35, and the width: 3 m
m × length: finish grinding wheels dimensions with a 10 mm, in this grindstone, speed: 50 m / min, horn pressure: 5 kg / cm 2, the condition subjected to grinding cast iron (FC25) in the grinding efficiency ( The specific material removal efficiency was measured and found to be 5 mm / min.
なお、比較の目的で、硬質粒子の材質をｃ・BN（立方
晶型窒化ほう素）とする以外は同じ条件で製造した研削
用砥石の場合は、同一の条件での研削で、1mm/minの研
削効果を示すにすぎなかった。For comparison purposes, in the case of grinding wheels manufactured under the same conditions except that the material of the hard particles is c-BN (cubic boron nitride), the grinding under the same conditions is 1 mm / min. It only showed the grinding effect.
第１表および第２表に示される結果から、本発明法１
〜６により製造されたｗ−BCN粉末１〜６は、いずれも
結晶粒径が20μｍ以上の粗粒であり、かつきわめて硬質
なので、これを用いて砥石を製造した場合、すぐれた研
削効率を示すことが明らかである。From the results shown in Tables 1 and 2, the method of the present invention 1
The w-BCN powders 1 to 6 produced by the methods 1 to 6 are all coarse particles having a crystal grain size of 20 μm or more, and are extremely hard, so that when they are used to produce a grindstone, they show excellent grinding efficiency. It is clear that.
上述のように、この発明の方法によれば、今迄全く注
目されず、したがって工業的規模での製造はほとんど行
なわれていなかったｗ−BCN粉末を、それも結晶粒径で2
0μｍ以上の粗粒の形で製造することができ、しかも製
造されたｗ−BCN粉末はきわめて硬質で、かつ欠け発生
のないものなので、例えば砥石の硬質粒子などとして適
用した場合にすぐれた性能を発揮するようになるなど工
業上有用な効果がもたらされるのである。As described above, according to the method of the present invention, w-BCN powder which has not received much attention so far, and thus has hardly been produced on an industrial scale, is also converted to a powder having a crystal grain size of 2%.
It can be produced in the form of coarse particles of 0 μm or more, and since the produced w-BCN powder is extremely hard and has no chipping, it has excellent performance when applied as, for example, hard particles of a grindstone. Industrially useful effects such as exerting are brought about.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) B01J 3/06 C01B 35/14 B24D 3/00 - 18/00 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. 6 , DB name) B01J 3/06 C01B 35/14 B24D 3/00-18/00
Claims (2)
％で、C:2〜20％、 N:40〜49％、 B:残り（ただし40〜49％） からなり、かつ20μｍ以上の結晶粒径を有することを特
徴とするウルツアイト型炭窒化ほう素粉末。The ratio of the constituent elements B, C and N is atomic%, C: 2 to 20%, N: 40 to 49%, B: remaining (but 40 to 49%), and A wurtzite-type boron carbonitride powder having a crystal grain size of 20 μm or more.
粉末を用い、これら原料粉末を、重量％で、 炭素粉末:2〜30％、 窒化ほう素粉末：残り、 の割合に配合し、混合した後、通常の高温高圧装置に
て、 温度:3000℃以上、 圧力:1万気圧以上、 の条件で加熱して、20μｍ以上の結晶粒径を有する六方
晶型炭窒化ほう素粉末を形成し、 ついで、この六方晶型炭窒化ほう素粉末に、10万気圧以
上の圧力で加圧処理を施して、ウルツアイト型炭窒化ほ
う素粉末に変態せしめること、 を特徴とするウルツアイト型炭窒化ほう素粉末の製造
法。2. Boron nitride powder and carbon powder are used as raw material powders, and these raw material powders are blended in a ratio of 2 to 30% by weight of carbon powder, boron nitride powder: remaining, and mixed by weight. Then, using a normal high-temperature and high-pressure apparatus, the temperature is heated to 3000 ° C. or more, the pressure is 10,000 atmospheres or more, and the hexagonal type boron carbonitride powder having a crystal grain size of 20 μm or more is formed. Then, the hexagonal type boron carbonitride powder is subjected to a pressure treatment at a pressure of 100,000 atmospheres or more to transform the powder into a wurtzite type boron carbonitride powder. Manufacturing method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2289831A JP2949827B2 (en) | 1990-10-26 | 1990-10-26 | Wurtzite-type boron carbonitride powder and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2289831A JP2949827B2 (en) | 1990-10-26 | 1990-10-26 | Wurtzite-type boron carbonitride powder and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04161240A JPH04161240A (en) | 1992-06-04 |
| JP2949827B2 true JP2949827B2 (en) | 1999-09-20 |
Family
ID=17748337
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2289831A Expired - Fee Related JP2949827B2 (en) | 1990-10-26 | 1990-10-26 | Wurtzite-type boron carbonitride powder and method for producing the same |
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| Country | Link |
|---|---|
| JP (1) | JP2949827B2 (en) |
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| CN106732726B (en) * | 2016-12-23 | 2019-08-02 | 阜阳师范学院 | A kind of photochemical catalyst CNB-BA and preparation method thereof |
| CN107117589B (en) * | 2017-05-25 | 2019-03-12 | 华侨大学 | A kind of high specific capacitance (BC) xNyOz material and its synthetic method |
| CN110721658B (en) * | 2019-10-15 | 2022-06-10 | 江苏索普（集团）有限公司 | Preparation method and application of hexagonal boron nitride-graphite phase carbon nitride intercalation composite material |
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1990
- 1990-10-26 JP JP2289831A patent/JP2949827B2/en not_active Expired - Fee Related
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| JPH04161240A (en) | 1992-06-04 |
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